Didi has been working to address consumer and government concerns over safety after a passenger was raped and killed by one of its drivers in August last year, about three months after another Didi user was murdered

SoftBank, which has holdings in several major cab hailing companies around the world, has also been a proponent of autonomous driving companies, and recently struck a deal with Toyota Motor Corp to develop automated driving.

While Son's seemingly random holdings perplex analysts, one consistent theme is his backing of the ride-hailing giants. SoftBank is among the biggest investors in Uber, China's Didi Chuxing, India's Ola and Singapore's Grab.

Dheeraj Hinduja, chairman at India’s second largest truck maker Ashok Leyland, prefers a low profile, but with managing director Vinod Dasari leaving at the end of the month, he says he’s become more “hands-on”.